Funny, the way you find out that a player like MatijaNastasic really matters in the "big picture" of Premier League football.

"What's the big deal about this guy?" you might be heard to say. "No goals, no assists in 20 games."

This past Saturday, though, the indicator was a throwaway exchange between two lame-duck commentators toward the end of a Premier League match that mattered far less in the table's order than either side hoped it would a few months ago.

Manchester City and West Ham United were putting the finishing flourishes on a well-contested but ultimately pretty routine late-season match at the Etihad.

City was en route to hammering down the last stakes claiming second place in the Premier League, no small achievement if you look at it from the perspective of the 18 teams beneath them, but far, far less than the club was aiming for when the season started in August.

West Ham was busy furthering its claim to "highest finisher among last season's promoted clubs," due in no small part to their late-in-coming realization that if "Robert Green" is the answer, you do not want to know the question as to your side's goalkeeping.

So anyway, Ian Darke was providing play-by-play and Steve McManaman was providing color—though let's be honest, Sir Ian provides as much color as play-by-play, particularly as the affair drones on—for one of the last ESPN Premier League broadcasts either is likely to do for quite some time.

And the subject turned to what was wrong with Manchester City, and why this expensively assembled club of mercenaries and savants had been afflicted with so much lack of quality, desire and so forth.

As the 79th minute wound down and after a prolonged silence, Darke asked McManaman blithely, "does City have to buy a lot in the summer?" McManaman roused from what seemed to be a waking slumber to harrumph, "no...I think they have to buy better quality from what they've bought."

Like any Manchester City fan needed to be reminded of the abject disaster that was last summer's transfer window.

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The play of Nastasic almost excuses the ineffectiveness of Javi Garcia. Almost.

Millions and millions of pounds spent on perpetually-limping Jack Rodwell, star-turned-squad player Javi Garcia and little boy lost Scott Sinclair.

Three strikes and City was out, while Manchester United landed Robin van Persie and with him another Premier League title.

They chatted on. "Only Nastasic of those that came last summer's come off so far," intoned Darke. McManaman enthusiastically agreed.

It was a passing reference in a stream of analysis, but it was telling. Especially since Nastasic did not even play for City against West Ham.

But this is what happens when you go from a little-heralded signing brought in ostensibly to provide for a future time when Joleon Lescott and even Vincent Kompany have gone to a mainstay on the back line in short order.

Maybe you remember, maybe not, but it was quite a debut Nastasic made for City. No big deal, really, just a Champions League match against Cristiano Ronaldo and Real Madrid.

You will definitely remember how the defense crumbled that evening, spitting up a late lead and turning it into a last-minute loss.

Players have been buried on benches at top clubs for far less significant sins than that. But Nastasic heard his name called again 11 days later at Craven Cottage for his Premier League debut. Then again in the Champions League against Borussia Dortmund four days later.

And then, after City's defense was gashed in Amsterdam by Ajax—with Lescott especially looking dodgy—Nastasic seized the starting job in late October at home against Swansea City and never let it go. Nastasic has made 20 appearances in the Premier League this season.

He started every one of those matches.

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Nastasic, stuck in again.

Nastasic, all of 20 years old, is now a linchpin of City's plans for the foreseeable future.

Later in the broadcast, McManaman noted that the likes of Lescott had a decision to make at City insofar as the Sky Blues already have a depth of quality on defense.

"It's going to be difficult, isn't it, for Manchester City because they have got Kompany, Nastasic...so of course there's going to be unhappy people there. It's whether they want to stay or whether they want to move on."

This is remarkable stuff, a comparative newbie walking into the first team and, by virtue of his excellent play, refusing to walk back out of it.

In a season where Manchester City's sky blue uniforms disguised a decidedly cloudy overall feeling, MatijaNastasic is a lone ray of bright light for a club concerned now only with the future.